• The Journal of Korea Robotics Society
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• v.17 no.2
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• pp.191-197
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• 2022

In this research, we developed the muscle-strength-assistant device, named as LEXO-W, and conducted suitability test for army when transporting high weights. LEXO-W relieves the burden when carrying heavy weights by distributing the load concentrated on the arms throughout the body. LEXO-W weighs 4 kg and is designed to handle objects weighing up to 55 kg. To verify the effectiveness of the device, object handling tests (high explosive shell, simple assembly bridges, and ammunition boxes) were conducted. Working time, metabolic rate, and electromyogram (EMG) signals were measured in each test. As a result, it was confirmed that the working time, metabolic rate and EMG signal before and after wearing LEXO-W were decreased. This research has great significance in that it verified the performance of the wearable device from the perspective of military operation.

• The Journal of the Society of Stroke on Korean Medicine
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• v.13 no.1
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• pp.77-85
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• 2012

Amyotrophic lateral sclerosis(ALS) is a progressive disorder that causes degeneration of motor neurons of the brain and spinal cord. It is characterized by loss of motor neurons leading to muscle weakness, and sensation and mental function stay intact during the course of the disease. Diagnostic tests include magnetic response imaging(MRI), electromyogram(EMG), muscle biopsy, and blood tests. In order to a definitive diagnosis of ALS, damage must be evident in both upper and lower motor neurons. When three limbs are sufficiently affected, the diagnosis is ALS. There is no cure for ALS. We experienced one case of ALS, the patients was diagnosed as ALS by EMG and symptoms. We diagnosed her as ShinEumHur(SEH) and treated by Choakwiyeum(左歸飮). We report the change of her symptoms through oriental medical treatment.

• Animal cells and systems
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• v.5 no.1
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• pp.31-35
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• 2001

Temperate-resident bats exhibit a circadian cycle of torpor and arousal In summer. The physiological role and selective advantage of torpor as an energy saving mechanism have been received much attention by hibernation biologists. However, despite the significance of the recovering euthermic function, the arousal process and mechanism in these animals have been poorly addressed. In this study, we investigated thermogenic and motor activities of a local bat species Murina leucogaster during arousal by simultaneously examining oxygen consumption rate, body temperature ($T_b$) and pectoral electromyography (EMG). We found that Tb of the torpid bats (12-14$^{\circ}C$) was augmented slowly by nonshivering mechanism during the initial awakening phase. The pectoral shivering, gauged by EMG activity, occurred between 17$^{\circ}C$ and 38$^{\circ}C$. Over this Tb range of shivering, heat was produced at a rate of 0.145 kcal $kg^{-1}\;min^{-1}$ to raise 1$^{\circ}C$ $T_b$ per min. Shivering was most intensive at 30-35$^{\circ}C$ where both EMG amplitude and spike frequency were the highest. Activation of the pectoral myofibers seemed to be controlled in a manner that motor units were recruited from smaller to larger sizes, with greater synchronization, as muscle shivering became intensive with increasing $T_b$.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.1
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• pp.41-50
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• 2014

The subjects of this study were 30 hemiplegia patients whose disease duration was over 6 months, and they were divided at random into a control group (n=15) receiving traditional rehabilitation therapy and an experimental group (n=15) receiving both traditional rehabilitation therapy and training using IT based EMG biofeedback. The program was applied for a total of 4 weeks. In order to examine the subjects' functional recovery, we measured their upper limb function using FMA and MFT, and activities of daily living using FIM before and after the training. Comparison between experimental groups in the study of upper extremity function improved after training in all tests was higher compared to the control group significantly (p<.05), but activities of daily living were not significantly different in. The results of this study were as follows. we concluded that stroke patients receving intensive IT based EMG biofeedback showed upper extremity functional recovery.

• Journal of Biomedical Engineering Research
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• v.41 no.2
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• pp.84-93
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• 2020

Despite of a lot of studies about proprioception tests, there are little study results to investigate the relationship between the functional movement and proprioception level. In this study, we tried to perform quantitative analysis for the effect of ankle joint proprioception level on the one leg standing postural control ability. Nine healthy people volunteered for this study. Force and position aspects of proprioception were evaluated using the electromyography system (EMG) and mobile clinometer application, respectively. The center of pressure (COP) trajectories, measured by a pressure mat sensor, were used for quantitative analysis of balance for each subject. We computed indices and errors of force and position aspects of proprioception from the EMG and ankle angle. Mean velocity of total and anterior-posterior direction (Vm and Vm_ap), root mean squared distance in anterior-posterior direction (RDap), travel length (L), and area (A) of COP trajectories were also calculated as indices of postural control ability of subjects. Two aspects of proprioception showed the low correlation from each other as previous studies. However, the EMG error of gastrocnemius lateral activation showed a high correlation coefficient with COP variables such as Vm (ρ=0.817, p=0.007), Vm_ap (ρ=0.883, p=0.002), RDap (ρ=0.854, p=0.003), L (ρ=0.817, 0.007) and A (ρ=0.700, p=0.036). Within our knowledge, this is almost the first study that investigated the relationship between proprioception level and functional movement. These study results could support that the ankle joint proprioception facilitation exercise would have positive effects on functional balance rehabilitation interventions.

• Safety and Health at Work
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• v.7 no.3
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• pp.237-243
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• 2016

Background: This study examined the relationship between interhandle distances and upper limb exertion during simply pushing and pulling of a cart with four swivel wheels, defined by a roll box pallet (RBP) in a Japanese industrial standard. Methods: Six healthy young male participants were asked to push and pull an RBP at a distance of 5.2 m under six conditions corresponding to different interhandle distances (40 cm, 60 cm, and 80 cm) and weights (130 kg and 250 kg). The upper limb exertion was studied by shoulder abduction and flexion, and elbow flexion, as well as surface electromyogram (EMG) in shoulder extensor, and elbow flexor and extensor. Participants were required to provide subjective evaluations on operability after each trial. Results: Subjective operability indicated that a narrower interhandle distance had a better operability for pushing. Interhandle distance was also related to upper limb exertion especially for pushing. A narrow interhandle distance caused smaller shoulder adduction but larger elbow flexion. The normalized EMG data revealed that muscular activity became smaller with a narrow interhandle distance in shoulder extensor. During the pulling task, elbow flexion was smaller at a narrow interhandle distance, although subjective operability and normalized EMG were not significantly varied. Conclusion: A wider interhandle distance, such as 80 cm, was not suitable in the forwardbackward movement of the RBP. Therefore, this study concluded that an interhandle distance of 40 cm would be suitable for pushing and pulling an RBP to protect the workers' hands against the risk of injury by installing inner handles.

• Journal of International Academy of Physical Therapy Research
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• v.3 no.1
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• pp.391-396
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• 2012

The purpose of this study is to identify which width of the base of support(BOS) is safer and more effective in lifting by comparing muscle activations and body sways when lifting objects under the width variation of the BOS. A total of fifteen healthy adults participated in this study. For the width variation of the BOS, the participants changed the width between their feet into three different types(10cm, 32cm, 45cm) and lifted a 10kg four times in each type after going up on a force plate. In order to measure body sways according to the width variation of the BOS, a motion analysis system was used. In addition, in order to measure the muscle activations of lower extremities, including the erector spinae, gluteus maximus, rectus femoris, and tibialis anterior, an electromyogram(EMG) analysis was employed. In addition, the Borg's scale was drawn by quantifying the subjective discomfort levels felt from each width of the BOS. In conclusion, no statistically significant differences according to the width variation of the BOS were observed(p=.295, .308)(p>.05). However, a statistically significant difference was exhibited between the Borg's scale, which indicates the discomfort levels from lifting performances, and the width variation of the BOS (p=$.000^*$).

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.261-268
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• 2014

This paper presents a electrocardiogram(ECG), electromyogram(EMG), and Photoplethysmography(PPG) signal wireless monitoring system based on Bluetooth Low Energy (BLE). ECG and EMG sensor interface analog front-end circuits are designed by using off-the-shelf parts. Texas Instruments(TI)'s CC2540DK is used for BLE-based communication. Two CC2540DK modules are used as Peripheral and Central nodes. In peripheral device, vital signals are acquired by the analog front-ends and fed to ADC for analog-to-digital conversion. The peripheral transmitts the data through the air to the central device. The central device receive the data and sends them to PC using UART. GUI is designed using Labview for displaying the acquired vital signals. The developed system can be used for future ubiquitous wireless healthcare system based on bluetooth 4.0.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.89-95
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• 2015

Compresses sensing (CS) technique is beneficial for reducing power consumption of biopotential acquisition circuits in wireless healthcare system. This paper investigates the maximum possible compress ratio for various biopotential signal when the CS technique is applied. By using the CS technique, we perform the compression and reconstruction of typical electrocardiogram(ECG), electromyogram(EMG), electroencephalogram(EEG) signals. By comparing the original signal and reconstructed signal, we determines the validity of the CS-based signal compression. Raw-biopotential signal is compressed by using a psuedo-random matrix, and the compressed signal is reconstructed by using the Block Sparse Bayesian Learning(BSBL) algorithm. EMG signal, which is the most sparse biopotential signal, the maximum compress ratio is found to be 10, and the ECG'sl maximum compress ratio is found to be 5. EEG signal, which is the least sparse bioptential signal, the maximum compress ratio is found to be 4. The results of this work is useful and instrumental for the design of wireless biopotential signal monitoring circuits.

• Journal of Biomedical Engineering Research
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• v.42 no.5
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• pp.225-231
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• 2021

The purpose of this study was to investigate the effect on the activity of the upper trapezius and erector spinae according to the length difference of the backpack using electromyogram (EMG). We also conducted a study comparing the center of pressure (COP) and weight distribution before and after using Wii® balance board. Thirty individuals were randomly assigned to the experimental group (n=14) wearing a backpack with a short right strap length and a control group (n=16) wearing a backpack with the same strap length. Data were collected by dividing into groups, carring a 15% weight backpack and walking for 20 minutes on a treadmill. As a result of analyzing the EMG data, there was no significant change in the upper extremity muscle activity of the control group, but it was significantly decreased in the right upper trapezius activity of the experimental group (p<0.05). In addition, there was a significant change of COP in the experimental group (p<0.05), but there was no significant difference of the weight distribution in both groups. Recognizing mechanical changes in the body that may occur due to the asymmetry of the strap length is thought to be helpful for systematic ergonomic intervention according to changes in the external environment in the future.